so a couple days ago i put a full msd ignition in and i also changed the intake manifold, my car strted right up after and it ran fine for two days i even drove it for and hour straight, the only thing that happened was that morning my fan wouldnt click on when the car heated up so i cut the positive to it and ran it to a switch. now today i went out and tried starting the car and it wouldnt start not even turn over the car just makes a clicking noise as if it were a dead battery or shorted out....so the next thing i did was had my cousin set me up to jump start it and the lights clicked on but it still only clicked never even cranked to try to start

Probably a bad starter. Check the connections (battery and starter dont just look as they may appear to be fine but not actually have a good connection) and make sure the batteries charged (many times if you just hook up the jumper cables and try to start it it wont start right away you have to let it charge because a dead battery is a huge load and so is a starter motor). Next thing ide do is either have the starter bench tested (many places will do this for free).

yeah i have to get that checked my thing is i never touched it when i did the work so thats why i dont understand that it would just go like that?

Then start with the easiest thing. Charge the battery or use a charger with a starter mode.
Are you sure you hooked the wiring up for the fan correctly? You may have just created a drain.

Well its funny how sometimes its coincidental. 99% of the rest of the time its related to something that was done but you have to start with the easy stuff first i guess. Unfortunetly in cases like this where there's no obvious answer nearly 99% of the time even if it was related to something that was done we wont figure out what specifically caused it till we find the problem and then well make the connection and say oh yea that would do it. Luckily the starting system is pretty simple. The thing is the click is the solenoid on the starter kicking in and that should cause the starter to engage. Since it dosnt we know that at least the 12V signal to the ignition switch is reaching the starter (thats what triggers the solenoid). Now we cannot yet confirm that the 12V supply to the starter is getting there nor that the starter has a good connection to ground or even that the battery has a good charge on it. In theory thats all thats really needed assuming there's a strong battery and the motors not seized or something. So its a good place to start check the connections, make sure the batteries charged, the starters ground is through the housing so as long as the motors ground strap is in place its hard not to have a good ground but you can test it, and lastly we can bench test the starter itself. Along the way something will creep up to tell us whats wrong and then we may find that what failed may have been the result of something that was done. My guess at this point though is that something that was installed is connected to a constant 12V supply or something when it should only have 12 when the cars running, it drained the battery, and now the battery dosnt have a strong enough charge on it to do much beyond a click. As I said it takes time to charge a battery and if the jumper cables were just hooked up to it and it was attempted to start the dead battery draws a lot of current, the starter draws a lot, and if there's any resistance in between the connections like the battery terminals like there commonly is it really starts to add it. keep in mind a truly "dead" battery with 0V across it is theoretically the same thing as a short circuit and will draw theoretically an infinite amounts of current as result. Realistically this obviously cant happen but but you can start to see just how much of a load a dead battery can be. On an interesting side note this is also why batteries can explode. This huge inrush of current to try and charge the battery can vaporize the electrolytes in the battery and the resulting pressure causes the battery to explode. This is why battery chargers are current limiting to slowly charge the battery.

1 check your battery connections u may have disturbed ur connection if ur hot wired the power to the battery
2 check fuses if you got power from them u may of blown a fuse or got a bad connection
3 check volts and do a load test to see if the battery is good, replace if so
4 if everything checks out go the starter route

yeah..i am going to do what you guys said i was in ct all day today so tomorrow around 10 ill be outside freezing checking all my connections first. then ill move and get the starter bench tested and we shall see from there

ok well i got my baby up and running today i went through and checked all my battery connections a couple were loose it had to be the PO cause it was places i have never touched then i bolted the battery up nice and snug and vroom started right up thank you guys i appreciate the help